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Whenever I see a correlation, I try to play the "reverse the direction of causality" game to look for other explanations.
Sometimes this gets nonsensical results ("people fated to get cancer crave cigarettes more than people who aren't fated to get cancer") but sometimes it opens up new explanations.
So maybe it works the other way around?
Perhaps people who make a lot more money are more likely to have traditional views of gender? They're rich enough that they can scoff at justice, and, in fact, ideas of equality and parity are threatening to them.
Patriarchs benefit from sexism.